Newcastle United are in talks to sign former Lyon captain Claudio Cacapa.
The Brazilian defender left the French champions at the end of last season after refusing to sign a new contract.
He has been holding discussions with The Magpies over the past few days and Sam Allardyce hopes to complete a deal for the centre-half.
"He is a top player and we will be delighted if we can pull this off as we regard him as a big capture," the Newcastle boss told the Evening Chronicle.
"Our fans should not be put off by the fact they may not have heard of Cacapa because he has certainly been heard of in Brazil and France.
"He has been captain of Lyon for the past five years and for every one of those five years they won the French title, so obviously he has a lot of Champions League experience.
"That's why we are hoping that everything goes okay with his medical and that we can agree a deal with his people because we believe he would be a terrific capture for us.
"Unfortunately, he has been back in Brazil and he has had no pre-season work, and in normal circumstances we would not consider him for our opening game at Bolton Wanderers a week on Saturday, but it all depends on what type of injuries we have."
Allardyce has been desperate to strengthen his defence over the summer, having only added David Rozehnal to his back-line to date.
Newcastle are also in talks to sign Alan Smith after agreeing a deal with Manchester United for the striker.